Surface coating material



Patented Aug. 26, 1952 1SURFACEYCOATINGQMATERIAL Daid fAl'ony, fMinneapolis; Mmm 'assigne'ritoh GeneralMill s;`Inc., a Vcorporatioxroi'iDelawal'e :Nnmawmg: `mmlieationomen/21,aan serial No. :122,847 i n ;The,.presentginventionrelates toalsurface coating material A.which similar in-natilremto when.

temperatures in ,order `to( clisperse `the .resin .in the dryingoiland-producea.homogeneous coating composition. .Theseoperations havefbeentedious `T batch operations carried-out .in-small kettles .re-

quiring extensivemlant facilities, and occupying ltheeguipmentfonlong periods .of time. `Moreover, during the cooking there Wasn` :tendency `for .thecomposition to Ldarken, depending npon the nature-of ithe drying-,oil and :theresin and -themethod sand exteiii'of` heating. .Furthermore, volatile solventsqare usually addedio 4hot `varnishcompositions .for .thelpurpose of4 Jreducing the viscosity. to fa brushable-consistency, .and

ffiiyf sommeinrthefsovent andflno nigh-:tempera ture-Elieating is'involved. Tlliewo'sinesteriisreadlily;'disselvedinithe solventfand this solution is "It is "therefore 'anj'obj ect "of-fthe 'present inven- *tion toprovidea novelsurfacevcoating compositionA containing a phenol formaldehyde resin ester,f"arus`in ester; anda-solvent. i "The-*phenol `'orinalldehy,de "resin 'esters 'employedrin the present'surface-coating"compositionare" those disclosed an'clwolainie'clinrmy -cofpending*application, *Serial INo: 803783, led March* 41949, entitled Phenolic ResinfEsters, "now abandoned As disclosed "therein, these esters f arev derived *from llilienol `formaliieliytie resins having a molecular weightf'within'theapoproximatefrange df `4501l900,"and'preferablywith- 'in the yaygiprox'imate range'of 5003100 These resins are thenl esteried 'withrl'iigh'eriunsaturated fifatty 'acids "derived from Vdrying foilsor Afrom {semi-'drying oils, such asflinseed oils-and soybean woil; "Thefresins may be water-'whitean'd crystalclear, and the resultant esterfmaybecolorless,

rdepenuing A:up-on the coior orme iratty acids/used 2 'for esterication. "The 'esters "themselvesjfto hard,ttough,. resilient lms, therate of dijyillg *beine dependent uponthe deereeio'f unsaturation `oftlieia'tty eniiemployed-` Y '"The resins used 'for :esterification` areipre'ler- `ably substantially ."free ifrom' methyll '.'groupsjor contain at mostonly a fewsucngroups. 1f there lare no "methylol groups present', there-'sfno chance for further .increase in the 'mleniilar Weight i of fthe resin throu'gh condensationwith itself during such esterifi'oation.' 'lhelesinsof this' typei-m'ay be madeloyslowly'adding :formaldehyde to an excess of" phenoltcoritaining'a 'ftd catalyst, 'and :then: carryingtout the usual L'acid catalyzed condensation. Afterlthe condensation is completed,` 'the `resin'mayb'e coolednnderjnitro- ,gen in whichevent it canbe madegWaterwvhite 'an'clLcrystal-clear.

Resins .the "molecular weight" range mentioned above may Lbe prepared` byemploying from f2" #to `3 .preferably from 2 `to"'2",1/2` mdle`s`,` f formalin ,per Ifour 'moles fof phenol` i .Resins *of "this type contain an average o'fabout'-4 toIO''lydroxyl' groupsper molecule; 'The process "issmple and inexpensive 'to conduct. Frexizess ihenolis readily (recovered, as are 1th` bisfai'fd tris compounds, all of 'which may beirecovered lby Simply distilling'ithem'ifromthe:resinous'reaction produc'tl 'The esterijcationimay be Acarried. ou'tjgin jaccordance withllthe teacliingsofmy coperidiilgllpplicat'rons, 'SeriaYNos 'lllg'll'liffiled Februanf i3. '1949, entitled Phenolic "Es'ters,` andMQ'TS; d "February "3, I9&9,i'entitledEstericationlPropeLSs. According 'to these aDDlcationsIthe Vresins Vlifay "be esteri'fied'hy heatingiamixture ofthewesm and "thefatty .acidsjn the absence ola Gitalyst at temperatures in excess :of2`0'0 J'Cgmreferaly from 230"250IC., `or thelpresence o'an estercation Y catalyst `at temperatures "from in 250 'CL "The .water "liberated" during thereajcti'on may 'be italien. of?, condensed, 'andthe reaction carried on until "tliepro'cluct^4 has ja yds'ired" acid number. A

Considerable Vvariation is possible bothfinthe types of resins .emblfoyed and the` estersjwtlo'h may beprepared 'from these resins. f Thus :simple phenol' formaldehyde resins as Well jajs `resiris prepared "from substituted i5henls havebejen shown t'o.j.produce desirable pro'ducts. It"`is"to vbe 'understoodthat the term p'fheno'l formalde- "hyderes`in is intended'to includelbothlthoseprge- 'pared `from'unsuiostituteol vphenol'saswell as'tl'iose 'prepared' from`'subs'tituted` 'phenols i ItWill "also be'-'apparent-"tnat thepreferredrange fpfmleeucomposition may also be of a wide variety. general,V the rosin acid esters of any polyhydricV lar Weight for the unsubstituted phenol formaldehyde resin is from 500 to 700. These resins have been found to work very saisfactorily ,with such semi-drying oil acids as soybean oil acids. When semi-drying oil acids are used with resins of molecular weight below 500 there is a tendency for the. ester to be slow in drying. For resins within this range of molecular weight, it is therefore preferred to employ `quicker drying fatty acids than soybean oil acids. Similarly, for resins having molecular weights within the range of 700-900, the fast drying oil acids and some of the semi-drying oil acids have a tendency toward the formation ofY gels during esterication. For use with this type of resin, therefore, it is preferred to use slower drying acids. Resins prepared from substituted phenols should have a correspondingly increased molecular Weight in view of the increased combining Weights of these phenols as compared with phenol itself. Y

` It is to be understood that soybean oil acids and linseed oil acids are merely given as typical examples of oil acids in the semi-drying and` drying oil classes. It will be apparent that other fatty acids in the semi-drying and drying oil groups can be used in place of those specifically mentioned.

' The rosin acid ester which is employed in the alcohol may be employed. Typical of these rosin acid esters are ordinary ester gum prepared from glyceroL'pentaerythritol rosin ester, and 2,2,6,6 f

brittle at high rosin ester concentrations, but f at the same time the 2,2,6,6-tetramethylolcyclohexanol rosin ester varnish compositions produce harder films at lower rosin ester concentrations than ydo the varnishes prepared from either glycerol orpentaerythrtolrosin esters. Accordingly, thetype of rosinester employed should be correlated both with'the quantity thereof, as Well as With the type of product desired.

It is usually found that less than 10% of the rosin ester does not appreciably change the character of the coating composition from the nature of the phenol formaldehyde resin ester. Accordingly, usually a minimum of 10% of the rosin ester is desirable. With some rosin esters, such as therosin ester of 2,2,6,6-tetramethylolcycloliexanol, therev is a tendency for extreme hardness and brittleness at concentrations substantially over 40%. Rosin ester concentrations up to 60% may be used, but the films obtained from such compositions are extremely hard and brittle and find utility chiefly on rigid articles VWhere flexibility of the film is nota critical factor. Where flexibility is a critical factor, usually about 40% is the maximum amount of rosin ester that may be employed. The percentages of rosin ester referred to herein are percentagesV OH number 13.

Y 4 by weight of the rosin ester based upon the total weight of rosin ester and phenol formaldehyde resin ester.

The usual varnish solvents may be used in these compositions. Typical of these are mineral spirits and xylene. The quantity of solvent which isemployed is subject to considerableV variation asis well understood in the trade. YThe solvent is usually employed in sufiicient quantity to produce the desired viscosity in the end product. Usually from 25-40% by weight of solvent based uponV the total weight of the composition is found satisfactory.

y In preparing the'composition the rosin ester is dissolved in the solvent. This may be accomplished at room temperature, but at thisV temperature it requires an extended period of time. Usually it is preferred to Warm the mixture of rosin ester and solvent and solution is readily effected in this manner. The solution may be effected readily'at temperatures below C., and does not involve any cooking. Io the solution of rosin ester in the solvent, the phenol formaldehyde resin ester may be added.

A short period of agitation is all that is required to produce a satisfactory finished product. Usually it is desired to add a small amount of oo nventional drier to the composition. This may be in the usual quantities employed. In vthe specific examples, 0.1% of cobalt as cobalt naphthenate was employed. It was found to give the fastest drying and the best hardness to the product. Other drier combinations which were employed include (A) 0.2% Pb, 0.02% Co;,.(B) 0.5% Pb, 0.05% Co; (C) 0.1% Mn; (D) 0.2% Pb, 0.02% Mn; (E) 0.7% Pb, 0.05% Co, 0.02% Mn. These percentages are all based on the Weight of the non-volatile materials in the composition.

The following examples will serve to illustrate the invention:

Example 1 VA phenol formaldehyde resin soybean oil ester was prepared as follows: 1504 g. of phenol and 4 g. of concentrated HC1 were heated to 80 C. Then 810 cc. formalin was added drop by drop for 5 hours andY 45 minutes. Refiuxing and agitation were continued 5 hours. Heating and agitation were resumed for 3 hours; then water and phenol were distilled at 7-30 mm. absolute pressure. After the phenol was distilled off, the bis-hydroxyphenyl methane was stripped at 10- 50 up to 225` C. `vapor temperature, 300 C'. pot temperature. The distillate weighed 181 g. The residue was cooled to 200 C. undernitrogen and poured. It weighed 1181 g. Its melting point was 107-113 C. l

300 g. of the above resin, 16 g. zincstearate, 906 g. soybean oil fatty acid, and cc. xylene were reiiuxed and agitated under a Stark and Dean tubefor 22 hours at 23o-270 C. The product was evaporated, then stripped to 250 C'. pot temperature at 50. The distillate weighed 121 g. The residue weighed 1047 g., l11,1330 1.5202. Y The acid number of the product (residue) Was v6.1,

'Three coating compositions were preparedas listed below. These were prepared from the above phenolformaldehyde resin soybean oil ester by dissolving the rosin ester in the solvent on a steam bath and by adding and dispersing'the phenol formaldehyde resin ester and the drier in the resultant solution. Y Y

- (A) A solution'of 20 g. ester gum and 24- g.

i phenol formaldehyde resin soybean oil ester and fshowninvth vI llowin table 05o:.drierffwamrepered'inrZYIzfermineral Spirits. n l. l j` 1 (39.1:.Azsolutionixoi' :20: .xapentaerythritol .rosin estense saphenol ,formaldehydeeresirrsoybean :oil estenand ricjc Cozdrer wasnprepared 1151.127 s. Lmineralspirits.:` Y

`(C) lArnineralgspiritsfsolntion containingy 241% ltetramethylolcyclolriexanol rosin ester. .3,6% :phe- 4:no1 formaldehydeiresi-n soybean: ester; 0.1%" Co :drierqand 39.9%:finineralyspirits Wasi-prepared.:

These coating compositions were then testedin theV conyentionalpzmannen and; the .f-results.. are

6 ihare beenzdescr-bedsothermodifications possible-without.departinggfrom the @spirit ofthe invention.; i Y. Y

I claim as my: invention;

.'5 l; A surface coating.compositionscomprisingea.

phenol formaldehyde resin ehighlyfesteriiiedfwith an unsaturated-'higher :fattyacid derivedifrom an oil having'at leastV semi-dryingfproperties; 'said resin-having a :molecular weight withinfthefapproximaterangeoff450900,1andfarosirracidffester ofk 1a' polyhydric alcohol, th'e rosirracid-festerbeing `employed inxthe `proportion ofiiromr.li60'%-of the-combined Weight of the .-ro'sin'acid esterand Lint Free.. .Teck FreetQIQil.. 6 hrs i Y l8(ldey) Swsrd Rocker Hardness 24 (2 days) 4916.415319.. Film Stability:

Boiling H90 0K 2 hrsm. `OK 2 hrsm. 721.11m amiamo-- '0K,;;.,...., DK: percent NaO`H 0K5 hrsw, `0K5 hrsi.--

Passed W' "Passed%" Flexibility: Mandrel Tes om ne; O

Passed 5/8.

Example-2.V l

` -A soybean'oilnestenoffaphenol formaldehyde 30 resin having a---meltingl-point of1^102-107H1Cifand i l Aa"mole'cul`ar Weight -of-16110, `iva-'s lprepared V-in the same mannerlras.tdcribddnpfExample 1. Four coating.: compositions were prepared from this esters respectively-the percentages being based on .-thetcombinedweight of the` soybean ester. and

"the rosi'ne'ster. lCobalt drier"(0 11%), Wasused inail cases. and -.50 lof mineral jspiritssolvent of these'coatirlg compositions were determined in the usual manner and the results ae'lsted' in the following table:

Percentage Rosin Ester in Vehicle Drying Time: 30min 30 min-- 30 min. No Transfer u ggmhirn n hnn?. Lint Free 3 s s.

k F ee to Foil 3% hrs 3% hrs 2% hrs. Tac r j 24 (l (11137)...Y 42 (l dey).-- 48 (1 day)..- 48 (l day). Sward Rocker Hardness 34 (3 dsys).. `38 (3 deys).. 55 (3 days) 60 (3 days).

38 (6days) Funisitiu'o 0K 2 hrs--- 0K 2 hrs cigfti and e. 72 Hrs. Cold HnO 0K OK OK 24 hrs..- OK 5 hrs-.. OK in 5 hours 5% NaOH butibrittle. Flexibility: Msndrel Test Passed Wh- Barely pass Barely pass i g 1" test. test.

` Errample 3 A White enamel was made as follows: The solid was composed of 52.5 parts by weight of titanium oxide (titanox RA), 28.5 parts of phenol formaldehyde resin soybean ester similar to those described in the previous examples, and 19 parts of 2,2,6,6tetramethylolcyclohexanol rosin ester. The solid constituents were dispersed in 31.5 parts of mineral spirits and 0.1% or cobalt drier was added. The mixture was then ground in a ball mill for 17 hours to produce a viscous, smooth white enamel of excellent drying properties and covering power. The iilm formed passed a mandrel test.

While numerous modifications of the invention alcohol, the rosin acid ester being employed in the proportion of from 10-60% of the combined weight of the rosin acid ester and the soybean oil fatty acid ester.

4i. A surface coating composition comprising a phenol formaldehyde resin highely esterified with linseed oil fatty acid, said resin having a molecular weight within the approximate range of 450-900, and a rosin acid ester of a polyhydric alcohol, the rosin acid ester being employed in the proportion of from 10-60% of the combined weight of the rosin acid ester and the linseed oil fatty acid ester.

5. A surface coating composition comprising a phenol formaldehyde resin, highly esteriiied with fa-comas .an unsaturated higher. Vfatty acid derived from :an oil having'at least semi-drying properties, said resin having a molecular weight Within the approximate range of 450-900, and a rosin acid ester ofv a polyhydric alcohol, the rosin acid ester `being employed in the proportion of from 10-40% of the combined Weight of the rosin acid ester and the unsaturated higher fatty acid ester. v

.6. A surface coating composition comprising a phenol formaldehyde resin highly esterified Withv soybean oil' fatty acid, said resin having a molecuglar Weight Within the approximate range of A50-900, and a rosin acid ester of 2,2,6,6tetra methylolcyclohexanol, the rosin acid ester being employed in the proportion of from 104.0% of the.

and the combined Weight of the rosin acid ester soybean oil fatty acid ester.v

'7. A surface coating composition comprising a phenol formaldehyde resin highly esteriedwithff soybean oil fatty acid, said resin having a molecular Weight Within the approximate range' ofv 450-900, and a rosin acid ester of glycerol, the

rosin acid ester being employed in the propor- Ithe combined-vveight of the rosinL acid esterjarid the linseed oil fatty acid ester.

tion of from lil-40% of the combined Weight of the rosin acid ester and the soybean oil fatty acid ester. Y

' 8. A surface coating composition comprising a phenol formaldehyde resin highly esterified with soybean oil fatty acid, said resin having -a molecular; Weight within the apiciroximate range yof 45.0-900, and a rosin acid ester of pentaerythritol, the rosin acid ester being employed in the proportion of from iti-40% of the combined Weight of the rosin acid ester and the soybean oil fatty :acid ester.

9. A surface coating composition comprising a .-fphenol formaldehyde resin highly est-erified with linseed oil fatty acid, said resin having a molecular Weight Within the approximate range of 45o-'900, and. a rosin acid ester of 2,2,6,6tetra vmethylolcyclohex'an'ol, the rosin acid ester being employed in the proportion of from lil-40% of the rosin acid ester being employed in the proportionof from l0-40% of the combinedj'w'eightef the rosin acidester and the linse'ed oil fatty acid 20Y ester.' y f DAVID AELONY. n

REFERENCES CITED A The follovvingr references are of record yin the file of this patent:

UNITED STATESPATENTS.. .I

Number Name Y Date 1,924,052 Somerville l- Aug; 22, 1933 2,091,965 v Cherry 1 Seme-7,1937 2,413,412 Mazzuc'chelli -1 Dec. 3l, 1946 Y FOREIGN PATENTS K n i Number Country Date 572,822 Great Britain Qct..25, 1945 OTHER REFERENCESY Mattiello, VProtective and Decorative Coatings, vol. I, 1941, p. 333. Y Y n Bakelite Varnish' Resins vTechnical Data, August [1935, Bakelite `Formula Suggestion `XVe-3433, April 16, 1935. 

1. A SURFACE COATING COMPOSITION COMPRISING A PHENOL FORMALDEHYDE RESIN HIGHLY ESTERIFIED WITH AN UNSATURATED HIGHER FATTY ACID DERIVED FROM AN OIL HAVING AT LEAST SEMI-DRYING PROPERTIES, SAID RESIN HAVING A MOLECULAR WEIGHT WITHIN THE APPROXIMATE RANGE OF 450-900, AND A ROSIN ACID ESTER OF A POLYHYDRIC ALCOHOL, THE ROSIN ACID ESTER BEING EMPLOYED IN THE PROPORTION OF FROM 10-60% OF THE COMBINED WEIGHT OF THE ROSIN ACID ESTER AND THE UNSATURATED HIGHER FATTY ACID ESTER. 